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Wave-Function Tomography of Topological Dimer Chains with Long-Range Couplings
F Pellerin1, R Houvenaghel2, W A Coish3
1Département de Physique, Université de Montréal, C.P. 6128, Succursale Centre-Ville, Montréal, Québec H3C 3J7, Canada.
Physical Review Letters
|May 17, 2024
Summary
Researchers engineered photonic dimer chains with tunable long-range hopping, generalizing the Su-Schrieffer-Heeger model. This enables precise control over topological phases of matter using synthetic gauge fields.
Area of Science:
- Condensed Matter Physics
- Quantum Optics
- Photonics
Background:
- Tailoring intersite connectivity in lattices is key for novel topological phases.
- Conventional models like Su-Schrieffer-Heeger are limited to nearest-neighbor couplings.
Purpose of the Study:
- To experimentally realize photonic dimer chains with tunable long-range hopping.
- To generalize the Su-Schrieffer-Heeger model with arbitrary hopping strength and phase.
- To explore topological phase transitions driven by synthetic gauge fields.
Main Methods:
- Utilizing a synthetic dimension scheme with frequency modes in an optical fiber loop.
- Directly accessing band dispersion and Bloch wave function geometry.
- Extracting the winding number for various configurations.
Main Results:
- Successful creation of photonic dimer chains with controllable long-range hopping.
- Demonstration of a generalized Su-Schrieffer-Heeger model.
- Observation of a topological phase transition induced by a synthetic gauge field.
Conclusions:
- This work provides a versatile platform for engineering topological bands in photonic lattices.
- The findings offer a route towards novel topological phases of matter.
- The system belongs to the AIII symmetry class, enabling specific topological properties.
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